The present invention relates to loading mechanisms which load and eject data storage media from the host unit, and in particular, to loading mechanisms which operate on cartridges such as disks which house the data storage media.
Loading mechanisms for storage data devices are known in the prior art. One such conventional loading mechanism is shown in FIG. 5. Such a loading mechanism may be utilized for loading floppy disk drives or optical disk drives. The mechanism includes a mounting frame 1 which mounts a data storage device within a host unit such as a personal computer or the like. A bezel 2 secured to mounting frame 1 is provided with a window 2a therein.
A main chassis 3 is mounted on frame 1. A guide rail 15 is supported on main chassis 3. A head 4 supported on guide rails 15 moves along guide rails 15 in the radial direction of the disk to perform seek operations along the disk. A spindle motor 5 mounted on chassis 3 is coupled to a spindle 6. A holder 7 holds the cartridge 9 therein. Holder 7 moves in the vertical direction of FIG. 5 within a space interval defined by position 7a and position 7b shown in phantom. Rubber vibration insulators 8 are disposed between mounting frame 1 and main chassis 3. Vibration insulators 8 absorb the vibration or shock of mounting frame 1 so that the shock or vibration is not transmitted to spindle motor 5, head 4 or other precision members of the disk operating portion of the data storage device.
A distance H extending from a top plane A of holder 7 to bottom plane B of mounting frame 1 represents the height of the data storage device. H is a generally standardized height determined for data storage devices. This height H is also utilized in conjunction with the invention.
During operation of the storage device, its power source is powered on. Cartridge 9 is then inserted through window 2a of bezel 2. In the prior art device, when no cartridge 9 is inserted, holder 7 is at position 7a with respect to main chassis 3. This is a commonly used configuration known in the prior art. As can be seen, the top of spindle 6 is separated from the bottom of holder 7 by a distance d. Therefore, when cartridge 9 is inserted, the bottom surface of cartridge 9 and the top of spindle 6 do not interfere with each other allowing smooth insertion of cartridge 9.
When cartridge 9 is completely within holder 7, holder 7 moves down to position 7b through an operation commonly used and well known in the art. When holder 7 moves, it follows that cartridge 9 also moves down and the disk which serves as the data storage medium within cartridge 9 is securely clamped at a prescribed height while maintaining concentricity with spindle motor 5. When cartridge 9 is inserted into holder 7, a shutter provided on holder 7 is opened so that a part of the disk inside the cartridge is exposed. A guide plate or iron, having a central bore is fixed to the exposed portion of the disk, in particular to the center of the disk. Therefore, as the cartridge starts to move downward, the guide plate is magnetically attracted by a permanent magnet of the spindle motor inside the turntable. The level of the attracting force increases as the cartridge is lowered. Even if there is a slight offset of the center of the disk from the center of the spindle 6, the disk is automatically centered and aligned with the center of spindle 6 since the disk hole is guided by the tapered guide surface on the end of spindle 6. A further downward movement of holder 7 increases the level of the magnetic attraction force so that the disk is brought into contact at its lower side with the top surface of the turntable, whereby the clamping of the disk is completed. Once the disk is clamped, spindle motor 5 begins rotating and head 4 is able to read information from or write information onto the disk either magnetically or optically through commonly used operations well known in the art.
If the entire data storage device is subjected to vibration or shock during a read or write operation, mounting frame 1 receives the vibration or shock. However, rubber vibration insulators 8 act as dampeners to prevent this vibration or shock from being transmitted to main chassis 3. Therefore, spindle motor 5, head 4 and the other precision members supported on main chassis 3 are not affected. For this reason, the data storage device operates normally even when subjected to vibration or shock during the read or write operation.
Cartridge 9 is ejected through a ejection button triggering mechanism known in the art. When this is done, holder 7 returns from position 7b to position 7a. Simultaneously, with the start of the rise of holder 7, cartridge 9, which has been lowered, starts to be lifted by holder 7 so that cartridge 9 lifts the clamped disk away from the turntable against the magnetic attracting force produced by spindle motor 5. The disk is then further raised together with cartridge 9. This separates the disk from spindle 6 by a gap d. The disk is ejected from the data storage device together with cartridge 9. In this state, the shutter on cartridge 9 is closed by a mechanism which is well known in the prior art, whereby the disk is completely covered by the shutter and the body of the cartridge.
The prior art apparatus has been satisfactory. However, when a cartridge 9 is inserted within the data storage device, there is a gap d between cartridge 9 and the top end of spindle 6. Therefore, the distance cartridge 9 and holder 7 travel from position 7a where the cartridge starts to move until the disk is clamped at position 7b by spindle motor 5 is normally about 5 mm. When vibration or shock is applied to the data storage device, rubber vibration insulators 8 flex resulting in vertical and/or horizontal displacement of main chassis 3, spindle motor 5, head 4 and other precision members mounted on main chassis 3. The amount of displacement is normally 2 to 3 mm, equaling about one half of the travel path.
The space above plane A and the space below plane B are spaces which must be utilized by the host unit (the personal computer or the like) in which the data storage device is utilized. Because component parts of the host unit are located within the spaces, no element of the data storage device may go beyond plane A or plane B even when there is vibration or shock. The height H must not be exceeded. Therefore, the prior art devices are constructed with a gap h having a height of 5 mm between plane A and the top of holder 7 at the position 7b. Additionally, a small gap h/2 is preserved between the plane B and the spindle motor or between the plane B and head 4. h/2 has a value of 2 to 3 mm which is large enough to prevent the bottoms of the spindle motor and head 4 from colliding with elements when the bottoms have projected downward beyond the bottom of the mounted frame in the event of the application of an external impact force during reading and writing operations. However, as discussed above, 2 to 3 mm must be provided for sufficient displacement clearance so space is wasted above holder 7. This must be counterbalanced with the standard height of the data storage device H even when holder 7 is at the upper position 7a, thus making it necessary to design cartridge 9, spindle motor 5, head 4 as well as other devices to be thinner to allow for this wasted space. This adversely affects the reliability of the data storage device. On the other hand, if too much emphasis is placed on the reliability, the size of the data storage device will unavoidably increase becoming larger than the standard height H. Accordingly, it is desired to provide a loading mechanism for data storage devices which minimizes the amount of wasted space without sacrificing reliability.